Fujitsu F2MC-8FX Manual Do Utilizador

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CHAPTER 3  REGISTERS
3.7
Direct Banks
The direct bank is in 0080
H
 to 047F
H
 of direct area, and composed of 128 bytes 
×
 8 
banks. The access that uses direct addressing and bit direct addressing in operand 
address 80
H
 to FF
H
 can be extended to 8 direct banks according to the value of the 
direct bank pointer (DP). The current bank is indicated by the direct bank pointer (DP). 
Direct Bank
Figure 3.7-1 shows the configuration of a direct bank. 
The access that uses direct addressing and bit direct addressing in operand address 80
H
 to FF
H
 can be
extended to 8 direct banks according to the value of the direct bank pointer (DP). The access that uses
direct addressing and bit direct addressing in operand address 00
H
 to 7F
H
 is not affected by the value of the
direct bank pointer (DP). This access is directed to fixed direct area 0000
H
 to 007F
H
.
Figure 3.7-1  Configuration of Direct Bank
Direct area
Memory
047F
H
0400
H
017F
H
0100
H
00FF
H
0080
H
007F
H
0000
H
Direct bank 7
(DP=111)
Direct bank 1
(DP=001)
Direct bank 0
(DP=000)
Fixed direct area
FF
H
80
H
7F
H
00
H
Direct addressing
and
Operand address 
in bit direct addressing